posted
Wayne's sugestion, as he told me, on how to perform the wall test are as follows: Put the vehicle on level ground, use a laser level with window sils to dertermine compliace. Car cannot have air let out of tires.
For you judges at this years finals, if a car passes the test, per Wayne, will you okay the car at finals?
I'd like some replys from World Finals Judges, because they will be the final say. People such as Raymon, Thor, Stefon, Sam, David, etc...
posted
Its not the "right way" to use a lazer, you can do some trick to go around that... I have told Wayne that before, but he like to use a messurement equipment do determine the all test...
I still like to use my eyes That is the best
-------------------- Tor Aamodt
*Head Judge at World finals 2004, 2006 and 2007 *Judge at World finals 2002 - 2003 *Norwegian dB Drag Racing Association. (NdBDRA) *Certified multi point judge.
posted
Tor, what you're telling me is that there is no definitive way to determine the wall line myself? Do I have to wait until finals to get your eye's opinion?
posted
A laser is 100 times more accurate than anyones eye. Think about it this way. When you look at an object behind another one; if you move up an inch or down an inch it will change the appearance of the height of the object behind it. I hope that made sense. With a laser you place it on the window sills and see where the laser lands. You can look at it laying down or standing up, but it won't change. If it hits something then there is a problem, if it doesn't then it's fine. Using your eyes on a wall test if like looking at an extreme vehicle and saying, "Yeah to my eyes that looks like 30 inches so it's ok." There are reasons we have measuring devices; so use them.
-------------------- Walkin' the dogs, and leadin' the puppies
posted
You cant only use the laser, you also has to look at how the cars "sits" on the ground. I can udjust my suspension, so i can build my box around 3 inch higher, if i can use the laser-test instead of common sense
posted
2004 Rules & Regulations: "6-5 The dBDRA defines a speaker wall as any subwoofer enclosure and / or baffle board that exceeds the height of an imaginary plane that stretches horizontally from the top of the driver’s door (where the side window enters the door frame) to the top of the passenger’s door on the opposite side of the vehicle.
Additional Guidelines: Compliance with this rule may be verified by using the following test: Two judges position themselves on opposite sides of the vehicle. A string (or wire) is passed through the open window on the driver’s side, through the interior of the vehicle, and out of the open window on the passenger side of the vehicle. Both judges should then pull the string so that it is taught while resting against the lowest point on the top of the 2 doors (where the glass enters the door frame). If the enclosure in question does not exceed the height of this string, then the enclosure is not considered to be a wall. If any part of the enclosure exceeds the height of the string, then the enclosure is considered a wall."
Therefore If any part of the enclosure exceeds the height of the string, taught while resting against the lowest point on the top of the 2 doors, then the enclosure is considered a wall.
A laser level accurately dertermines relative height, the eye cannot as explained by "Trouble". If the enclosure is not higher that the string, shown by a laser level, it is legal for Street per 2004 Rules & Regulations.
posted
A lazer WILL NOT WORK. NOTHING WORKS. eyes are the best thing to use. If you use a lazer level, your waisting your time.
Reason: yeah, a lazer level can be used to line up both drivers and passenger window seals.
but if a lazer level is off it wont work. if your off at .2" at 1ft then your off .8" at 10ft.
The best way to do it is too have a lazer attaced to a tripod outside the vehicle. you make sure the lazer is perfectly level in all directions. you lower the lazer untill it lines up with the door seals. Then you turn the lazer level to point at the enclosure. if it touches, its illegal.
the problem is using bubble levels. What might appear to be level may actually not. I have tried this at home. The problem is still the use of the human eye. The difference can be 1-2" @ 10ft away and still seem level on a bubble level.
Here is a better way and a more accurate way to determin this:
run a string through the windows. if doing this by yourself you can tape the string to the outside of one door. Use tape measure outside the vehicle touching the ground. When you lower the string down to touch the other door run the string outside the vehicle on the tape measure. When the string toughes the door seal make note of the placement on the measuring tape ( 38" for an example )
Now, tape that string to the other door. Now you have a string running from door/window seal to the other. Now take another piece of string and tie around that one and run it out the back of the vehicle over the enclosure. Use the measuring tape again off the ground. Lower the string untill it touches the box. If the string touches the box and your below the 38" example your legal. If its more, your illegal.
Lazers are good if you can get them 100% perfectly level.
Also, lazers may be level in one direction, but if you turn them 90 degrees, your on a different angle and your level needs re adjusted.
By far, the eyeball is the best way to do it.
Another way is to place a tape measure inside the vehicle w/ the enclosure. kneel down and eyeball the window seals then turn your eyes to the tape measure. What ever # you see is how tall you can build your box. BUT, the wieght of the box will lower the back in making the box not as tall as you could build it, but thats ok, cause now your legal.
I hope this helps,
-------------------- See you in the lanes,
dBSteve Get Loud Productions LLC Posts: 8492 | From: Midwest | Registered: Aug 2000
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posted
I found that running a string across the driver and passenger doors then placing a steel flat ruler on the enclosure and sliding it toward the string was a pretty good way to verify my enclosure height.If it hit or was over then not legal. My box is relatively level so slope was not an issue.
How does that work with the tape measure if I drop my rear bags when you are measuring? Posts: 1674 | From: Michigan | Registered: Nov 2002
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quote:Originally posted by dBSteve: A lazer WILL NOT WORK. NOTHING WORKS. eyes are the best thing to use. If you use a lazer level, your waisting your time.
Reason: yeah, a lazer level can be used to line up both drivers and passenger window seals.
but if a lazer level is off it wont work. if your off at .2" at 1ft then your off .8" at 10ft.
The best way to do it is too have a lazer attaced to a tripod outside the vehicle. you make sure the lazer is perfectly level in all directions. you lower the lazer untill it lines up with the door seals. Then you turn the lazer level to point at the enclosure. if it touches, its illegal.
the problem is using bubble levels. What might appear to be level may actually not. I have tried this at home. The problem is still the use of the human eye. The difference can be 1-2" @ 10ft away and still seem level on a bubble level.
Here is a better way and a more accurate way to determin this:
run a string through the windows. if doing this by yourself you can tape the string to the outside of one door. Use tape measure outside the vehicle touching the ground. When you lower the string down to touch the other door run the string outside the vehicle on the tape measure. When the string toughes the door seal make note of the placement on the measuring tape ( 38" for an example )
Now, tape that string to the other door. Now you have a string running from door/window seal to the other. Now take another piece of string and tie around that one and run it out the back of the vehicle over the enclosure. Use the measuring tape again off the ground. Lower the string untill it touches the box. If the string touches the box and your below the 38" example your legal. If its more, your illegal.
Lazers are good if you can get them 100% perfectly level.
Also, lazers may be level in one direction, but if you turn them 90 degrees, your on a different angle and your level needs re adjusted.
By far, the eyeball is the best way to do it.
Another way is to place a tape measure inside the vehicle w/ the enclosure. kneel down and eyeball the window seals then turn your eyes to the tape measure. What ever # you see is how tall you can build your box. BUT, the wieght of the box will lower the back in making the box not as tall as you could build it, but thats ok, cause now your legal.
I hope this helps,
Exatly....
This is way to difficult for me to write... So thanks Steve... We are agree
-------------------- Tor Aamodt
*Head Judge at World finals 2004, 2006 and 2007 *Judge at World finals 2002 - 2003 *Norwegian dB Drag Racing Association. (NdBDRA) *Certified multi point judge.
posted
Actually, I was told by Wayne that the angle of the vehicle is to be considered. For example, a person could lower the rear of a van; thus, allowing them to build a taller box than say another person that has the exact same vehicle. So, in order to make sure this doesn't happen, Wayne said the following is how a vehicle in question should be "wall tested":
1. Use a level to get the angle of a vehicle.
2. Take a lazer level mounted to a tripod and angle it to be even with the vehicle.
3. Set the tripod in the vehicle and even it up with the lowest point of the front window seals.
This way obviously is dependent upon the lazer level to be accurate, but if this organization can manage to set a lazer level, then it has serious issues.
Just thought I would let you know what Wayne's input was a few months ago; however, you may want to call and make sure.
Later,
Jason Meyer
-------------------- 2004 SS 1-2NW World Champion 2005 World Finals SS 1-2NW 2nd Place 2006 World Finals SS 1-2NW 3rd Place Team Maxxsonics Member of Broken Silence Competition Team Posts: 194 | From: Sedalia, MO, USA | Registered: Aug 2000
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posted
So in NW is the top of the rubber window seal the point which the enclosure must be under or is it the door panel itself? I have heard it both ways.
Posts: 1674 | From: Michigan | Registered: Nov 2002
| IP: Logged |
posted
I can't believe some people have such a hard time using a laser and a level. I'll tell you what, come to our manufacturing plant and tell them that your eyes are more accurate than the lasers we use. HAHA It's a very simple step that can be done in less than a minute on any vehicle. No need to run multiple strings or tape things here and there.
-------------------- Walkin' the dogs, and leadin' the puppies
quote:Originally posted by Trouble: I can't believe some people have such a hard time using a laser and a level. I'll tell you what, come to our manufacturing plant and tell them that your eyes are more accurate than the lasers we use. HAHA It's a very simple step that can be done in less than a minute on any vehicle. No need to run multiple strings or tape things here and there.
Ok, then explain how to use a lazer to determine if a box is too tall or not.
-------------------- See you in the lanes,
dBSteve Get Loud Productions LLC Posts: 8492 | From: Midwest | Registered: Aug 2000
| IP: Logged |
quote:Originally posted by DD Shreder: You move it until bubble is between the two lines.
The problem with that is even with the bubble inbetween the two lines, you can still move the level/lazer and keep the bubble between the lines. If your level and lets say 4' off the ground at the lazer, you might be 4'3" @ 10ft away with the bubble still inbetween the lines and appear level. This is the problem with lazers/bubble levels.
-------------------- See you in the lanes,
dBSteve Get Loud Productions LLC Posts: 8492 | From: Midwest | Registered: Aug 2000
| IP: Logged |
posted
My level is calibrated to be accurate within one inch at 120 feet. So at 10 feet you're going to be off a maximum of 1/12 of an inch. And mine's only a $13 level, much better are made.
I'd like to see an eye set level with accuracy of 1/12 of an inch at 10'.
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